Harri Kauhanen first talked about what he mean by cloud ecosystem. During the next 45 minutes, we built, published and load tested a real-time note taking application using Ruby on Rails 3 and services like Heroku, MongoHQ, Google Font Directory, Pusher and BrowserMob.

The key message of this presentation is that “whatever you mean by this cloud stuff, the main benefit for me is that I don’t spend my energy on building infra — instead I can concentrate on creating awesome applications”.

The service is live at http://futu-stickies.heroku.com/ and the sources (with the actual commit history from the demo) is available at this Github repository.

PS: The XSS vulnerability discovered by my wonderful audience was due I used auto_link method. Normally, anything like <%= note.text %> is escaped automatically by Rails 3, but to my surprise <%= auto_link note.text %> is not.